Finally, a thread that combines my only two areas of expertise, drinking beer and mindlessly watching trains…
First, along the NCRR (soon to be five Amtrak trains per day)
Charlotte: Divine Barrel Brewing (not much food) divinebarrel.com
Lexington: Southern Lunch (excellent lunch counter, parking beside tracks but you can’t really see trains from inside)
https://southernlunchcatering.food-pi.com/
Lexington: Goose and Monkey Brewing: gooseandthemonkeybrewhouse.com (former furniture mill)
Greensboro: Natty Greens Downtown (ask for patio seat — best railfan spot on NCRR in terms of trains per hour)
Raleigh: Wye Hill Brewing (they are sticklers for reservations. You want the patio rail. overlooks Union station)
https://wyehill.com/. (Bonus: rooms above the 8th floor at the downtown Marriott have very good views of Union station operations)
And a random spot in Michigan (4? Wolvereens per day):
Ypsilanti: Sidetrack Bar and Grill sidetrackbarandgrill.com